PART III.] Dr. Cobbolds Nematoid Ova Parasites. 619 



been suffering from hsematuria associated with the distomum hcematobiuTn, refers 

 to the circumstance that he obtained from the patient some other urinary parasites 

 in the egg condition.* " On five separate occasions," writes Dr. Cobbold, " I obtained 

 one or more specimens of the eggs or embryos of a minute nematode. In one 

 instance there were about fifty of these ova in the urine, their embryonic contents 

 being well developed, and in a state of activity. Usually they were all in this 

 advanced condition; but on the 25th of July, 1870, several were observed in much 

 earlier stages of development." The fully grown eggs gave a longitudinal measure- 

 ment of 5^^" by ToW i^ breadth. Judging from the description of the ova and their 

 contained embryos, it would seem that the parental form must have been oviparous. The 

 embryos, when freed artificially from the egg, measured ''' "" in length by " in breadth. 



On two occasions free dead specimens were observed which had been lying in water some 

 time, and these measured ^i^" by ^^V^ • The parents of the patient had mentioned that 

 the latter had " passed three small vermiform entozoa by the urethra." * 



Fig. 61. — Ova and freed embryos of an oviparous nematode ; obtained in urine. (After Cobbold.) 



Dr. Cobbold writes : " I have been thus particular in recording these facts, because 

 future discoveries may enable us to identify the species of nematode to which these ova are 

 referable. I know only one set of observations on record which refer to this same species 

 of parasite." The parasite referred to is the above-cited trichina cystica. As it may be a 

 convenience to future observers to be able to judge of these matters for themselves in the 

 absence of the original papers, I have reproduced Dr. Cobbold's illustrations, together with 

 a reduced outline of Dr. Salisbury's figure. The reduction has been affected by means 

 of a camera lucida, so as to represent the helminth as magnified 300 diameters instead 

 of 1,000 as in the original. This will facilitate comparison with Dr. Cobbold's figure 

 representing his nematoid ova parasites f (Fig. 61). Notwithstanding the discrepancy in 

 size. Dr. Cobbold considers that the helminths are referable to one and the same species.| 

 They are both manifestly the offspring of some oviparous nematode ; further than that it 

 is, I think, hardly safe to carry the comparison. 



The figures which also serve to elucidate another matter, as Dr. Cobbold has since 



* During the last seven years I must have examined the sediment of very many gallons of chylous urine, 

 but never observed any ova of nematodes, though, from time to time, I have found many hundreds of 

 embryos. 



t British Medical Journal, July 27, 1872, page 92. 



X London Medical Becord, No. i, vol. i, 1873 ; The Lancet, July 13, 1878, p. 64. 



